Numbered Publications by Katherine VanValin
ASC-265: Estrus Synchronization Protocols for Beef Females
Les Anderson, Darrh Bullock, Kevin Laurent, Jeff Lehmkuhler, Katherine VanValin | Oct. 11, 2024 (New)
Artificial insemination (AI) can be an effective tool for beef producers to use to make faster genetic progress in the herd. Unlike the dairy industry where cattle are handled multiple times a day, incorporation of AI can be difficult because beef cattle are not handled often or easily. Decades ago, scientists began developing methods to control the expression of estrus to decrease the amount of labor and time required for AI. An understanding of estrus synchronization protocols can be beneficial to producers considering using AI in their genetic program.
ASC-266: Reproduction in the Bull
Les Anderson, Darrh Bullock, Kevin Laurent, Jeff Lehmkuhler, Katherine VanValin | Oct. 11, 2024 (New)
The fertility of the herd bull is essential to a successful cow-calf operation. In many respects, it is more of a concern than the fertility of a single cow. Sub-fertile bulls create lower calving rates and can be responsible for poor herd-weaning weights: For every heat cycle a female fails to conceive, there is a corresponding decrease in calf weaning weight from 25 to 45 pounds because of a younger calf being weaned. It does not take long to realize that poor fertility or infertility of a bull can be extremely expensive to the cow-calf producer.
ASC-263: Converting from Year-round to Controlled Calving
Les Anderson, Darrh Bullock, Ben Crites, Kevin Laurent, Jeff Lehmkuhler, Katherine VanValin | Jul. 19, 2024 (New)
In the United States more than half (55%) of all beef cow-calf operations do not have a defined calving season. Typically, in these operations, bulls are not removed from the herd and remain with the cows the entire year. This "uncontrolled breeding" results in cows calving over several months or, in some cases, cows calving every month. Calving year-round presents many challenges in herd management and decreases productivity. In some cases, producers have an off-the-farm job and limited time can be left to dedicate to the cowherd. In these scenarios, it is crucial to maximize time and labor efficiency.
ASC-264: Artificial Insemination in Beef Cattle
Les Anderson, Darrh Bullock, Kevin Laurent, Jeff Lehmkuhler, Katherine VanValin | Jul. 19, 2024 (New)
Successful artificial insemination (AI) breeding programs depend on adequate facilities, good herd health programs, sound nutritional management, using experienced and well-trained technicians, high fertility semen, and the ability to observe or synchronize a fertile estrus. Most problems and(or) failures in AI programs are associated with poor nutritional development in replacement heifers, inadequate body condition of cows at and after calving, failure to identify or control estrus in females, and/or failure to breed them at the proper time. Rarely is infertility the result of poor-quality semen or technician error.
ASC-258: Minerals Matter for Beef Cattle
Michelle Arnold, Kevin Laurent, Jeff Lehmkuhler, Katherine VanValin | Nov. 20, 2023 (New)
Minerals are an essential nutrient for beef cattle. If minerals are not consumed in the diet, deficiencies can occur. At the same time, overconsumption of certain minerals can result in toxicity. Providing the proper balance of each mineral without overconsumption is necessary for optimal performance, as minerals are essential for supporting growth, reproduction, lactation, and health.
ASC-260: Controlling Reproduction in Female Yaks
Les Anderson, Jeff Lehmkuhler, Mary McCarty, Katherine VanValin | Oct. 26, 2023 (New)
The yak (bos grunniens) is a member of the bovine family and plays a vital role in the life of the people of the Himalayan region (China, Mongolia, India, Nepal, etc). The Himalayas is an especially harsh region with long, cold winters and sparse vegetation for most of the year. As with all bovine, nutrient availability, both quality and quantity of available foodstuffs, and current status of body reserves or degree of fat stored in the body dictate the ability of the cow to conceive during a breeding season. Even though conception rate (probability of conception at a single estrus event), is high (70+%), pregnancy rate (probability of conception at the end of a breeding season) is typically only 40%-60% in their natural environments because a high proportion of female yaks fail to have an estrus during the breeding window. Understanding the major factor reducing pregnancy rate is important to creating and implementing management protocols to improve the reproductive ability of female yaks.
ASC-259: Reproduction in Female Yaks
Les Anderson, Jeff Lehmkuhler, Mary McCarty, Katherine VanValin | Oct. 26, 2023 (New)
The yak (Bos grunniens) is a unique domestic animal. These animals were developed in the extreme environment of the Himalayas, where food resources can be extremely limiting. The yak provides food (meat and milk), fiber (hair), and are beasts of burden (used for pack, transportation, plowing, etc.) for the local populations. The number of yaks in the world is limited, creating a need to understand and control reproduction in the yak to improve genetic diversity.
ASC-249: Reading the Fine Print: Understanding Mineral Tags
Jeff Lehmkuhler, Katherine VanValin | Jul. 18, 2022 (New)
Among the variety of supplementation options currently available for beef cattle operations, a mineral can be one of the most challenging to select. Mineral tags contain important information regarding the contents of a mineral supplement and are regulated by the Association of American Feed Control Officials (AAFCO). Understanding the information on a mineral tag will aid in the comparison of multiple products and help to ensure the selected mineral product will meet the needs of specific animals.
ASC-248: Vitamin Supplementation for Beef Cattle
Les Anderson, Darrh Bullock, Kevin Laurent, Jeff Lehmkuhler, Katherine VanValin | Jul. 18, 2022 (New)
Beef cattle have defined requirements for vitamins. In some instances, vitamin supplementation may be necessary to avoid deficiencies. Vitamins are classified into two categories: water-soluble and fat-soluble. Water-soluble vitamins include the B vitamins, such as riboflavin, thiamin, and niacin, as well as vitamin C. Fat-soluble vitamins include vitamins A, D, E, and K. Supplementation for beef cattle generally focuses on vitamins A and E. This is because the rumen microbes synthesize the water-soluble vitamins and vitamin K in sufficient quantities to avoid deficiencies. Vitamin D requirements can often be met by exposure to the sun and would therefore only be of concern for cattle in confinement housing.
ASC-245: Feeding Soybeans to Beef Cattle
Jeff Lehmkuhler, Katherine VanValin | Mar. 24, 2021 (New)
Various factors such as delayed planting, early frost, drought or suppressed market prices may lead one to consider feeding soybeans to cattle. Soybeans can be fed to beef cattle as an energy and protein source. Depending upon the stage of development, soybeans will have varying degrees of feed value and a feed test for nutrient content is recommended.
